The present invention relates to cover systems, particularly for hauling vehicles, such as dump trucks.
Many hauling vehicles, such as dump trucks, include open-topped containers useful for hauling or storing various materials. For example, in a typical dump truck application, the dump body is used to haul a variety of particular material, such as asphalt, gravel, aggregate or similar products. Other hauling vehicles carry organic materials, such as grain or produce.
Depending upon the nature of the materials stored in the open-topped container, it is often desirable to provide a cover for the container. Of course, rigid covers are well known that may be hinged from end of the container body. These rigid covers have gradually given way in the trucking industry to flexible tarping systems because the flexible tarpaulin can be easily stowed when a cover is not necessary, such as when the dump truck is being loaded. Moreover, the flexible tarp is much easier to deploy than a rigid cover, and is easier to replace when it becomes worn or damaged. Furthermore, in some instances the flexible tarp provides a tighter environmental seal for the contents of the container than is provided by a rigid cover.
A variety of tarping systems have been developed that are geared to particular hauling vehicle applications. One cover system particularly suited for open-topped containers on hauling vehicles is the EASY COVER® tarping system, marketed by Aero Industries, Inc. The EASY COVER® tarping system includes a U-shaped bail member that is pivotally mounted at its end to the base of the container body. The horizontal section of the U-shaped bail is attached to the tarp, while the free ends of the vertical elements are pivotably mounted to the truck body. In certain applications, the EASY COVER® tarping system includes an actuation mechanism that automatically pivots the U-shaped bail member to deploy the tarp over the load within the open-topped container. When the actuation mechanism is released, it automatically pivots the bar, thereby unfurling the tarp from the tarp roller at the front of the vehicle. A hand crank or powered motor can be provided to rotate the tarp roller to retract or wind the tarp when it is desired to open the container top.
The EASY COVER® tarping system is generally illustrated in FIG. 1. A vehicle 10 includes an open-top dump body 12 that is covered by a flexible cover system 15. The cover system includes a tarpaulin cover 16 that is shown in its deployed position spanning the length of the container and covering the load within. The tarp cover 16 is wound onto a retraction mechanism 19, which is in the form of a roller assembly, to stow the cover when not in use. The retraction mechanism 19 is typically supported on a cab protector 13 that overhangs the cab of the truck 10. A wind deflector 14 can be provided in a variety of configurations ranging from a simple deflector plate to a housing that substantially encases the retraction mechanism 19.
An extension mechanism 17 is utilized to pull the tarp 16 across the container body 12. The extension mechanism 17 includes the U-shaped bail member 22 that includes a horizontal bar 24 to which the free end of the cover or tarp 16 is attached. The extension mechanism 17 also includes a pivoting mechanism 25, such as a spring pack, that rotates the bail member 22 toward the back of the dump body 12.
In the EASY COVER® tarping system and similar powered systems, the extension mechanism 17 operates to deploy the cover 16, while a separate mechanism operates to retract the cover against the force of the extension mechanism. Thus, the retraction mechanism 19 includes a drive motor 20 that rotates the roller of the retraction mechanism to wind the cover onto the roller. The drive motor 20 is reversed or disconnected from the retraction mechanism roller to allow the pivoting mechanism 25 to pivot the bail arms to their deployed position.
A manually deployed tarping system for use with dump trucks is the Easy Pull® tarping system, also produced by Aero Industries, Inc. As depicted in FIG. 2, The Easy Pull® system 30 includes a flexible tarp 31 that is wound around a spool 34 at one end of a dump bed. The spool 34 includes its own retraction mechanism, such as a torsion spring arrangement (not shown) that drives the spool to retract the cover. A wind deflector 14 can be provided to protect the spool and wound tarp.
With this type of system, the cover is manually unwound against the retraction mechanism of the spool 34. In particular, a rope 40 attached a pull bar 38 at the free end of the tarp is used to unwind the tarp from the roller to extend along the length of the dump bed. Anchors 42, 43 are provided at the front and back ends of the dump bed 12 around which the pull rope 40 is wound for storage. In use, the pull rope is removed from the front anchor 43 and carried to the end of the dump body 12. As the rope 40 is manually pulled, the cover is extended across the load. Once the cover is in its deployed position, as shown in FIG. 2, the pull rope 40 can be tied off on the rear anchor 42.
The cover or tarp 31 is configured to include flaps 32 that overhang the sides of the dump body 12. The flaps 32 are typically pulled tight by tension cords 36 that are weaved through openings in the flaps and wrapped around anchors on the sides of the dump bed. The flaps are important (and even mandated by some state regulations) when hauling certain materials, such as asphalt.
The nature of the hauled material can dictate the type of cover 16 or 31 that is used to cover the load within the dump body 12. In the case of asphalt, the tarp is formed of a heavy duty vinyl material. For other applications, such as hauling gravel, the cover is formed of a mesh material.
The different tarp or cover requirements for different loads can be problematic, requiring either the use of a different truck outfitted with the necessary cover system, or the replacement of the cover system on a particular truck with the necessary tarp. Neither option is very desirable. What is needed is a system for covering an open-topped vehicle container that allows for ready substitution of the tarp or cover spanning the load.